The present invention relates to tires and, more particularly to a tire having two wires in each bead.
It is known to provide tires with two bead wires in order to avoid rotation of the tire on the rim or to prevent loosening of the bead of the tire on a pressure loss. Such embodiments are described, for example, in EP-A 168,754 and in JP-A 5,178,033.
The tire according to EP-A 168,754 is intended to be mounted on a rim, at least one bead seat of which is axially extended inward by an axial retention projection (called hump). The bead of that tire contains two wires, one of which is close to the toe of the bead, toward the inside of the tire, and the other ensures locking of the first in case of strong axial stresses. The two wires are preferably integrated by a carcass fabric to improve that cooperation. The resistance to loosening is therefore due essentially to the action of the second wire on the first, and the anti-loosening action is not always sufficient.
JP-A 5,178,033 describes a secondary wire applied against the rim, under a main wire or beside the main wire, in order to improve radial uniformity by avoiding eccentricity defects. That requirement is not involved in the problems of loosening.